This collection includes items related to Florida’s environments, ecosystems, and species. It includes the subcollections of Florida Cooperative Fish and Wildlife Research Unit project documents, the Sea Grant technical series, the Florida Geological Survey series, the Coastal Engineering Department series, the Howard T. Odum Center for Wetland technical reports, and other entities devoted to the study and preservation of Florida's natural resources.

AN EVALUATION OF MANATEE DISTRIBUTION PATTERNS
IN RESPONSE TO PUBLIC USE ACTIVITIES
IN KINGS BAY, CRYSTAL RIVER, FLORIDA

Cheryl A. Buckingham

Florida Cooperative Fish and Wildlife Research Unit
117 Newins-Ziegler Hall
School of Forest Resources and Conservation
Institute of Food and Agricultural Sciences
University of Florida, Gainesville, FL 32611

This paper is to be cited as Buckingham, Cheryl A. 1990. An evaluation of manatee distribution
patterns in response to public use activities in Kings Bay, Crystal River, Florida. Florida Cooperative
Fish & Wildlife Research Unit, University of Florida, Gainesville. 49 pp.

Table 5. Total number of boats and people per boat counted as they
passed the observation stations on the nine weekdays surveyed. Average
number of people per boat was calculated by dividing the total number
of boats by the total number of people for each boat size category.

Boats People
Boat Size X of ALL % of ALL People/
Category Number Average/day Boats Number Average/day People Boat

Table 6. Total number of boats and people per boat counted as they
passed the observation stations on the thirteen weekend days and
holidays surveyed. Average number of people per boat was calculated
by dividing the total number of boats by the total number of people for
each boat size category.

Boats People
Boat Size % of ALL % of ALL People/
Category Number Average/day Boats Number Average/day People Boat

Table 8. An estimate of the number of people in the study area engaging
in each activity on an average morning, weekday or weekend/holiday.
This was calculated by averaging the product of the maximum number of
boats in the study area in each size category during the aerial surveys
and the proportion of people engaged in each activity calculated from
data from the three observation stations.

Table 9. Estimated level of public use for the entire study area for
November 1, 1988 through March 12, 1989 calculated by averaging the
product of the maximum number of boats from aerial surveys and the
average number of people per boat from the combined observation station
data. There were 84 weekdays and 48 weekend days and holidays during
this period.

Fig. 8. Minimum average water
temperatures for each survey day.
Time e*lapoI between Survey days varis.

1 2 3 4 5 1 2 S 4 6 7 8 10 1 121 151 17 20

Fig. 9. Average water temperatures
over morning hours.

Temperature ( F)
71.41

71.2

71

70. -

70.6 -

70.4

T9 -

1

7-8 am

8-9 am

9-10 am

10-11 am 11-12 am

Fig. 10. Proportion of South Bay manatees in South Bay sanctuaries
as a function of water temperature and boat count. A contour of
the fitted response surface generated by the equation:

Logit of probability of a 15.09 0.2264 x (water temperature)
manatee in the south bay 0.03924 x (number of boats
being in the sanctuary in south bay)

For a given water temperature on the Y-axis, choose the
proportion of manatees in sanctuaries that may indicate boat
avoidance by manatees (e.g. over 50%), follow a horizontal line
from the temperature to the selected proportion and follow a
perpendicular line down to find the maximum number of boats. For
example, the proportion of manatees in the south bay using the
sanctuaries would be expected to reach 50% at 68 degrees F when 8
boats were in the south bay.

75.0-

.2

.3
S72.8

o .5
I..

70.5

'. .7
a

.8
z 68.3

66.0 4
0.0

18.5 33.0 49.5 66.0

Number of Boats in south bay

Fig. 11. Number of people per boat
weekdays vs. weekends in study area
age Number of Peope per Boat

mall Medium Large Total

C] WeIday Em Weekend
(Inoleds all 3 eoervatln station.)

Fig. 12. Estimated number of boats in
study area. Weekdays vs. Weekend days
Maximum no. In each category ach day.

30-

20
10

Small Medium Large Total

M Weekday ~ Weekend

(From aerial urvey data.)

Fig. 13. Average number of people/day
in each boat size category.

Medium Large

SlWeekday jf Weekend

Fig. 14. Est. no. of people engaged
in each activity Weekdays vs. Weekends